Emergency guide for Nethermind client

One-page interactive complete emergency guide for Nethermind client.

Disclaimer

This guide is for informational purposes only. The author nor website owner does not guarantee accuracy of the information in this guide and is not responsible for any damages or losses incurred by following the guide.

Database corruption

In a case of database corruption (shortly DB corruption):

  1. Stop Nethermind service

    sudo systemctl stop nethermind

  2. Delete and recreate Nethermind directory

    Delete the directory 
    sudo rm -r /var/lib/nethermind
    Recreate the directory 
    sudo mkdir -p /var/lib/nethermind
    Set directory ownership 
    sudo chown -R nethermind:nethermind /var/lib/nethermind

  3. Start the service

    sudo systemctl start nethermind
    Check the service 
    systemctl status nethermind
    journalctl -f -u nethermind

Once the execution chain will get synchronized, your validator will go online again.

Nethermind got stucked

If a Nethermind got stucked, you can simply restart it.

sudo systemctl restart nethermind

This can be also automated through Service Log Monitor.

There are no other serious issues with Nethermind detected.